blob: 5f275a0b31e428e5f5139ad0abbab9d89d0886a8 [file] [log] [blame]
/*
This file is part of drd, a data race detector.
Copyright (C) 2006-2008 Bart Van Assche
bart.vanassche@gmail.com
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
This program is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307, USA.
The GNU General Public License is contained in the file COPYING.
*/
#include "drd_clientobj.h"
#include "drd_error.h"
#include "drd_mutex.h"
#include "priv_drd_clientreq.h"
#include "pub_tool_errormgr.h" // VG_(maybe_record_error)()
#include "pub_tool_libcassert.h" // tl_assert()
#include "pub_tool_libcbase.h" // VG_(strlen)
#include "pub_tool_libcprint.h" // VG_(message)()
#include "pub_tool_machine.h" // VG_(get_IP)()
#include "pub_tool_threadstate.h" // VG_(get_running_tid)()
// Local functions.
static void mutex_cleanup(struct mutex_info* p);
static Bool mutex_is_locked(struct mutex_info* const p);
// Local variables.
static Bool s_trace_mutex;
static ULong s_mutex_lock_count;
// Function definitions.
void mutex_set_trace(const Bool trace_mutex)
{
tl_assert(!! trace_mutex == trace_mutex);
s_trace_mutex = trace_mutex;
}
static
void mutex_initialize(struct mutex_info* const p,
const Addr mutex, const MutexT mutex_type)
{
tl_assert(mutex != 0);
tl_assert(p->a1 == mutex);
p->cleanup = (void(*)(DrdClientobj*))&mutex_cleanup;
p->mutex_type = mutex_type;
p->recursion_count = 0;
p->owner = DRD_INVALID_THREADID;
p->last_locked_segment = 0;
}
/** Deallocate the memory that was allocated by mutex_initialize(). */
static void mutex_cleanup(struct mutex_info* p)
{
tl_assert(p);
if (s_trace_mutex)
{
VG_(message)(Vg_UserMsg,
"[%d/%d] mutex_destroy %s 0x%lx",
VG_(get_running_tid)(),
thread_get_running_tid(),
mutex_get_typename(p),
p->a1);
}
if (mutex_is_locked(p))
{
MutexErrInfo MEI = { p->a1, p->recursion_count, p->owner };
VG_(maybe_record_error)(VG_(get_running_tid)(),
MutexErr,
VG_(get_IP)(VG_(get_running_tid)()),
"Destroying locked mutex",
&MEI);
}
sg_put(p->last_locked_segment);
p->last_locked_segment = 0;
}
static void not_a_mutex(const Addr mutex)
{
MutexErrInfo MEI = { mutex, -1, DRD_INVALID_THREADID };
VG_(maybe_record_error)(VG_(get_running_tid)(),
MutexErr,
VG_(get_IP)(VG_(get_running_tid)()),
"Not a mutex",
&MEI);
}
static
struct mutex_info*
mutex_get_or_allocate(const Addr mutex, const MutexT mutex_type)
{
struct mutex_info* p;
tl_assert(offsetof(DrdClientobj, mutex) == 0);
p = &clientobj_get(mutex, ClientMutex)->mutex;
if (p)
{
return p;
}
if (clientobj_present(mutex, mutex + 1))
{
not_a_mutex(mutex);
return 0;
}
p = &clientobj_add(mutex, ClientMutex)->mutex;
mutex_initialize(p, mutex, mutex_type);
return p;
}
struct mutex_info* mutex_get(const Addr mutex)
{
tl_assert(offsetof(DrdClientobj, mutex) == 0);
return &clientobj_get(mutex, ClientMutex)->mutex;
}
/** Called before pthread_mutex_init(). */
struct mutex_info*
mutex_init(const Addr mutex, const MutexT mutex_type)
{
struct mutex_info* p;
if (s_trace_mutex)
{
VG_(message)(Vg_UserMsg,
"[%d/%d] mutex_init %s 0x%lx",
VG_(get_running_tid)(),
thread_get_running_tid(),
mutex_type_name(mutex_type),
mutex);
}
if (mutex_type == mutex_type_invalid_mutex)
{
not_a_mutex(mutex);
return 0;
}
p = mutex_get(mutex);
if (p)
{
const ThreadId vg_tid = VG_(get_running_tid)();
MutexErrInfo MEI
= { p->a1, p->recursion_count, p->owner };
VG_(maybe_record_error)(vg_tid,
MutexErr,
VG_(get_IP)(vg_tid),
"Mutex reinitialization",
&MEI);
return p;
}
p = mutex_get_or_allocate(mutex, mutex_type);
return p;
}
/** Called after pthread_mutex_destroy(). */
void mutex_post_destroy(const Addr mutex)
{
struct mutex_info* p;
p = mutex_get(mutex);
if (p == 0)
{
not_a_mutex(mutex);
return;
}
clientobj_remove(mutex, ClientMutex);
}
/** Called before pthread_mutex_lock() is invoked. If a data structure for
* the client-side object was not yet created, do this now. Also check whether
* an attempt is made to lock recursively a synchronization object that must
* not be locked recursively.
*/
void mutex_pre_lock(const Addr mutex, const MutexT mutex_type,
const Bool trylock)
{
struct mutex_info* p;
p = mutex_get_or_allocate(mutex, mutex_type);
if (s_trace_mutex)
{
VG_(message)(Vg_UserMsg,
"[%d/%d] pre_mutex_lock %s 0x%lx rc %d owner %d",
VG_(get_running_tid)(),
thread_get_running_tid(),
p ? mutex_get_typename(p) : "(?)",
mutex,
p ? p->recursion_count : -1,
p ? p->owner : DRD_INVALID_THREADID);
}
if (p == 0)
{
not_a_mutex(mutex);
return;
}
tl_assert(p);
if (mutex_type == mutex_type_invalid_mutex)
{
not_a_mutex(mutex);
return;
}
if (! trylock
&& p->owner == thread_get_running_tid()
&& p->recursion_count >= 1
&& mutex_type != mutex_type_recursive_mutex)
{
MutexErrInfo MEI = { p->a1, p->recursion_count, p->owner };
VG_(maybe_record_error)(VG_(get_running_tid)(),
MutexErr,
VG_(get_IP)(VG_(get_running_tid)()),
"Recursive locking not allowed",
&MEI);
}
}
/**
* Update mutex_info state when locking the pthread_mutex_t mutex.
* Note: this function must be called after pthread_mutex_lock() has been
* called, or a race condition is triggered !
*/
void mutex_post_lock(const Addr mutex, const Bool took_lock)
{
const DrdThreadId drd_tid = thread_get_running_tid();
struct mutex_info* p;
p = mutex_get(mutex);
if (s_trace_mutex)
{
VG_(message)(Vg_UserMsg,
"[%d/%d] post_mutex_lock %s 0x%lx rc %d owner %d%s",
VG_(get_running_tid)(),
drd_tid,
p ? mutex_get_typename(p) : "(?)",
mutex,
p ? p->recursion_count : 0,
p ? p->owner : VG_INVALID_THREADID,
took_lock ? "" : " (locking failed)");
}
if (! p || ! took_lock)
return;
if (p->recursion_count == 0)
{
const DrdThreadId last_owner = p->owner;
if (last_owner != drd_tid && last_owner != DRD_INVALID_THREADID)
{
tl_assert(p->last_locked_segment);
thread_combine_vc2(drd_tid, &p->last_locked_segment->vc);
}
thread_new_segment(drd_tid);
p->owner = drd_tid;
s_mutex_lock_count++;
}
else if (p->owner != drd_tid)
{
VG_(message)(Vg_UserMsg,
"The impossible happened: mutex 0x%lx is locked"
" simultaneously by two threads (recursion count %d,"
" owners %d and %d) !",
p->a1, p->recursion_count, p->owner, drd_tid);
p->owner = drd_tid;
}
p->recursion_count++;
}
/**
* Update mutex_info state when unlocking the pthread_mutex_t mutex.
* Note: this function must be called before pthread_mutex_unlock() is called,
* or a race condition is triggered !
* @return New value of the mutex recursion count.
* @param mutex Pointer to pthread_mutex_t data structure in the client space.
* @param tid ThreadId of the thread calling pthread_mutex_unlock().
* @param vc Pointer to the current vector clock of thread tid.
*/
void mutex_unlock(const Addr mutex, const MutexT mutex_type)
{
const DrdThreadId drd_tid = thread_get_running_tid();
const ThreadId vg_tid = VG_(get_running_tid)();
struct mutex_info* const p = mutex_get(mutex);
if (s_trace_mutex)
{
VG_(message)(Vg_UserMsg,
"[%d/%d] mutex_unlock %s 0x%lx rc %d",
vg_tid,
drd_tid,
p ? mutex_get_typename(p) : "(?)",
mutex,
p ? p->recursion_count : 0);
}
if (p == 0 || mutex_type == mutex_type_invalid_mutex)
{
not_a_mutex(mutex);
return;
}
if (p->owner == DRD_INVALID_THREADID)
{
MutexErrInfo MEI = { p->a1, p->recursion_count, p->owner };
VG_(maybe_record_error)(vg_tid,
MutexErr,
VG_(get_IP)(vg_tid),
"Mutex not locked",
&MEI);
return;
}
tl_assert(p);
if (p->mutex_type != mutex_type)
{
VG_(message)(Vg_UserMsg, "??? mutex 0x%lx: type changed from %d into %d",
p->a1, p->mutex_type, mutex_type);
}
tl_assert(p->mutex_type == mutex_type);
tl_assert(p->owner != DRD_INVALID_THREADID);
if (p->owner != drd_tid || p->recursion_count <= 0)
{
MutexErrInfo MEI = { p->a1, p->recursion_count, p->owner };
VG_(maybe_record_error)(vg_tid,
MutexErr,
VG_(get_IP)(vg_tid),
"Mutex not locked by calling thread",
&MEI);
return;
}
tl_assert(p->recursion_count > 0);
p->recursion_count--;
tl_assert(p->recursion_count >= 0);
if (p->recursion_count == 0)
{
/* This pthread_mutex_unlock() call really unlocks the mutex. Save the */
/* current vector clock of the thread such that it is available when */
/* this mutex is locked again. */
thread_get_latest_segment(&p->last_locked_segment, drd_tid);
thread_new_segment(drd_tid);
}
}
const char* mutex_get_typename(struct mutex_info* const p)
{
tl_assert(p);
return mutex_type_name(p->mutex_type);
}
const char* mutex_type_name(const MutexT mt)
{
switch (mt)
{
case mutex_type_invalid_mutex:
return "invalid mutex";
case mutex_type_recursive_mutex:
return "recursive mutex";
case mutex_type_errorcheck_mutex:
return "error checking mutex";
case mutex_type_default_mutex:
return "mutex";
case mutex_type_spinlock:
return "spinlock";
default:
tl_assert(0);
}
return "?";
}
/** Return true if the specified mutex is locked by any thread. */
static Bool mutex_is_locked(struct mutex_info* const p)
{
tl_assert(p);
return (p->recursion_count > 0);
}
Bool mutex_is_locked_by(const Addr mutex, const DrdThreadId tid)
{
struct mutex_info* const p = mutex_get(mutex);
if (p)
{
return (p->recursion_count > 0 && p->owner == tid);
}
return False;
}
int mutex_get_recursion_count(const Addr mutex)
{
struct mutex_info* const p = mutex_get(mutex);
tl_assert(p);
return p->recursion_count;
}
/**
* Call this function when thread tid stops to exist, such that the
* "last owner" field can be cleared if it still refers to that thread.
*/
void mutex_thread_delete(const DrdThreadId tid)
{
struct mutex_info* p;
clientobj_resetiter();
for ( ; (p = &clientobj_next(ClientMutex)->mutex) != 0; )
{
if (p->owner == tid && p->recursion_count > 0)
{
MutexErrInfo MEI
= { p->a1, p->recursion_count, p->owner };
VG_(maybe_record_error)(VG_(get_running_tid)(),
MutexErr,
VG_(get_IP)(VG_(get_running_tid)()),
"Mutex still locked at thread exit",
&MEI);
p->owner = VG_INVALID_THREADID;
}
}
}
ULong get_mutex_lock_count(void)
{
return s_mutex_lock_count;
}